The present invention relates to a gas discharge tube, and more particularly to a gas discharge tube of high density material and an arc column producing a high intensity light source for spectroscopy, chromatography, or the like.
Low pressure high intensity arc lamps are typically made of quartz or glass which requires labor intense multiple glass transitions between the light output window and the body of the lamp to compensate for the large difference in thermal expansion between the body material and the window. When the gas within the lamp is Deuterium, such body material is not dense enough to eliminate the slow loss of the gas because of the permeability of the body material to Deuterium. The loss of Deuterium may also occur through window material used in the lamp. In order to extend the useful operational life of the lamp against the slow loss of Deuterium, the lamp wall and window are typically coated with a ceramic or glaze which reduces the gas permeability of the overall structure. The loss of Deuterium may be addressed by including a large amount of Nickel in the internal construction, which Nickel is presaturated with Deuterium prior to sealing the lamp with its final fill pressure. The slow release of Deuterium from the Nickel into the lamp replenishes of the lost Deuterium. Unfortunately, this process is labor intensive, requires many different materials, and uses gas permeable materials requiring special coatings. Additionally, control of the arc ball of currently manufactured Deuterium lamps is difficult and in some cases requires multiple DC sources.